Recombinant CD74 polypeptides

Abstract

Disclosed are recombinant CD74 polypeptides mutated relative to the naturally occurring CD74 polypeptides with improved properties such as binding of CD74 ligands such as MIF and RTL1000 as well as polynucleotides that encode the polypeptides, expression vectors comprising the polynucleotides, bacteria that include the expression vectors, and methods of making the recombinant polypeptides.

The invention claimed is: 
     
       1. A recombinant polypeptide comprising: the amino acid sequence of SEQ ID NO: 1 or SEQ ID NO: 3. 
     
     
       2. The polypeptide of  claim 1 , further comprising a label, the label comprising a fluorescent dye, an enzyme, a protein tag, a fluorescent protein, or biotin. 
     
     
       3. The polypeptide of  claim 1 , wherein the polypeptide consists of the amino acid sequence of SEQ ID NO: 1 or SEQ ID NO: 3.